Réponse :
A = ( - 5 + 1 ) + ( 6 - 11 ) + ( - 3 - 17 )
A = -4 + ( - 5 ) + ( - 20 )
A = -4 - 5 - 20
A = -9 - 20
A = -29
B = ( 15 - 12 ) - ( - 1 - 8 ) + ( 5 + 7 ) - ( - 1 - 5 )
B = 3 - ( - 9 ) + 12 - ( - 6 )
B = 3 + 9 + 12 + 6
B = 12 + 12 + 6
B = 24 + 6
B= 30
